Insulating lacquer and material.



PAUL BOERCHE, OF LONDON, ENGLAND.

INSULATING LACQUER AND MATERIAL.

specification of Letters Patent.

Patented Jan. 29, 1907.

Application filed March 26, 1906. Serial No. 307,990.

To all whmn it may concern:

Be it known that 1, PAUL BOERCHE, a citi- Zen of the Republic of France,residing in London, N., England, have invented certain new and usefulImprovements in Insulating Lacquer and Material; and I do hereby declarethe following to be a full, clear, and exact description of theinvention, such as will enable othersskilled in the art to which itappertains to make and'use the same.

This invention relates to an improved insulating-lacquer for the coatingof wire, sheets, and other metal surfaces, either for the purpose ofprotecting such surfaces against dampness or other chemical action orand 1110 re, especially for insulating electrical wires, cables, moldedpieces, and the like, thus taking the lace of the more expensive rubber,silk, an similar insulating-coverings. I am using for this purpose aresidue obtained in candle in anufactories from the distillation ofstearin and known to commerce as stearinpitch, which normally is softand can be easily dissolved and melted, showing adhesive properties. Ihave, however, ascertained that this material when ex osed to atemperature above 220 centigra e changes its nature and hardens into aninsulatinglacquer which can neither be melted nor dissolved. I can usethis material either by itself or together with resinous substances,linseed-oil, oil of turpentine, asphalt, litharge, and other substances,according to the special application it is intended for. In the firstcase the stearin-pitch may be solved in benzol or other suitablesolvent, and when mechanically freed. from impurities by filtering orthe like this solution may be used for covering metal surfaces which areafterward exposed to a temperature between 225 and 285 centigrade,avoiding overheating, which renders the lacquer brittle. During thisheating the solvent evaporates, leaving a uniform covering ofinsulating-lar ucr on the metal surface. The coated surfaces after immersion in the solution may be moved vertically upward between radiators orother heating surfaces, the temperature of which may inthe heat from anysource Whatever, and in some cases an electric current with suitableresistances may be passed through the metal-- for instance, a wiretorapidly perform the drying.

Obviously the thickness of the desired coating may be varied, accordingto the desired purpose or degree of thickness, by thickening thesolution or by repeatedly coating or by more rapidly drying, &c. Thesolution also may be painted on with a brush, or the stearinpitch may beused in a semiliquid or viscous state, or articlesfor instance, forelectrical use as a substitute for ebonite, vulcanized rubber, &c.-maybe entirely made from stearin pitch and then exposed toa temperature of220 to 285centigrade.

What I claim is 1. The process of converting soft stearinpitch intoinsoluble and unmeltable material having insulating properties whichconsists in heating the stearin-pitch to a temperature above,approximately, 220 centigrade, substantially as described.

2. The process of converting soft stearinpitch into insoluble andunmeltable material having insulating properties which consists inheating the stearin-pitch to a temperature between, approximately, 220centigrade and, approximately, 285 centigrade, substantially asdescribed.

3. The process of forming an insulatingcoating on surfaces to beinsulated consisting. in applying thereto a coating of. stearinpitch andthereupon heating the coating to a temperature above, approximately, 220centigrade, substantially as described.

4. The process of forming an insulatingcoating on surfaces to beinsulated consisting in first dissolving stearin-pitch and then applyingto the surface acoating of the dissolved stearin-pitch, and thereuponheating the coating to a temperature above, approximately, 220,substantially as described.

5. The process of forming an insulatingcoating on bodies to be insulatedconsisting of applying thereto a coating of stearin-pitch and thereuponexposing the thus-coated body to a temperature above, approximately, 220cent-igrade, substantially as described.

6.-The process of forming an insulating IOC coating on bodies to beinsulated consisting have hereunto set my hand this 10th day of v inimmersing the same in a bath of stearin- March, 1906.

pitch and then moving the body so coated vertically near a source ofheat having a ter'ni 5 perature above, approximately, 220 centi-Witnesses:

grade, substantially as described. GASTON FAVIER,

In testimony that claim the foregoing I I H. D. JAMESON.

PAUL BOEROHE.

